Microprocessor-based electrical power distribution equipment such as switchgear, switchboards, panelboards, and motor control centers accumulate considerable amounts of information concerning the electrical distribution systems to which they are connected, as well as the power equipment itself. Today's energy monitoring systems provide end-users with the capability to remotely monitor a variety of equipment via automatic monitoring devices. This allows more accurate data and decreases human resource requirements. Industrial automation, monitoring, energy management, and control systems include many microprocessor or microcontroller-based monitoring devices that communicate with each other, as well as with other computers, via various communications protocols such as the Ethernet for a local area network or the MODBUS® (hereafter “Modbus”) communication protocol. The Modbus communication protocol is used with various slave devices that respond to read and write requests from a master controller. Among the features provided by this communication protocol is a means for the user to access data from either an RS-232 or RS-485 serial connection from the slave device to the master controller.
Recently, communications to a data collection system from monitoring devices has been implemented over a network using an Ethernet protocol, wrapped in a TCP/IP format, which provides the ability to access these devices from potentially anywhere via a network. Typically, monitoring devices such as meters are connected to points in an electrical distribution system and obtain data from that point in the electrical distribution system. The meter is also connected to the data collection system via the network. Therefore, configuration is required in multiple places in the energy monitoring system. The meter is configured with detailed information required for the connection to the meter from the data collection system. The configuration information may be the mode of the meters, communications parameters, identification information, or other information required for the correct interpretation of the data collected by the meter. Conversely, configuration of the data collection system is required in order to access the meter and use the data sensed by the meter.
Currently energy consumers who wish to monitor their energy use through an energy monitoring system employ many different personnel who are responsible for meter configuration, installation, and monitoring. In addition, personnel must be employed to configure the data collection system for new meters. The time and resources necessary to configure a meter and the data collection system also result in lost data if the time period between installation and configuration exceeds the capacity of the meter to record data.
Additionally, a Modbus network can have multiple slave devices on a common network, such as a common RS485 network. The slave devices can communicate at up to 38.4 kbps. Modbus master devices can poll a slave device at a very high rate to the point a Modbus slave's idle time can diminish to zero for certain periods of time. This can potentially lead to system resets or shut down tasks that users can configure to free up available bandwidth. With Ethernet gateways communicating Modbus TCP/IP with multiple connections, it is possible for a large number of outside devices to want to poll the slave devices. Many times, these outside devices are asking for the “same” data. These multiple requests for the same data tie up network resources and negatively affect network performance.